"It´s not a lake - it´s a river"

uwepetercom.blogspot.de/2014/03/s-u-sp-e-ns-io-n-f-e-rry-r-e-ndsb-u-rg.html Binnenalster | Hamburg | Germany | 2014-08-10
The Binnenalster or Inner Alster Lake is one of two artificial lakes within the city limits, which are formed by the river Alster. Origin: wikipedia